Band Wheels

[EZ]

Hi Guys,
My band wheels are aluminum, which there is'nt any thing wrong with them, right now. I have a set of steel wheels that I can put on if some thing wood go wrong with the aluminum ones. I was just wondering if there wood be a different in the way the saw wood cut. When I saw 2x12 oak it's slow going, I wonder with steel wheels if I wood have more tork. Both sets are the same dia.
EZ

[Tom]

This is strictly an opinion but I don't think you would see too much difference.  Most of the torque benefit you would get from heavier wheels would even out after you got into the initial cut and the engine was depended upon to drive the blade.

The most important piece of the cutting tool is the blade. If the machine is spinning the blade at the recommended feet per minute then which machine you use doesn't matter.

In wider cuts, blade speed would be my first suspect.but I would look at slippage before I would be concerned with wheels.  Slippage at the clutch or drive belts, and slippage of the blade on the surface of the wheel are the primary places to look.  

Initial blade speed might even be a concern but, here again, I would look at engine RPM or "gearing" or undersized engine before I would suspect the blade wheels.

Steel would definitely not be as prone to damage or wear as aluminum and that may be a big plus down the road.

My experience with my 38 horse kubota and 24 horse Onan and observing smaller engines on other's mills leads me to believe that Horsepower is the most directly attributable attribute to cutting speed after the blade.

Anyplace that the saw can "rub off" horsepower will slow you up.  Blade wheels not being co-planer and lined up will rob horsepower.  They can be configured to run the blade and still not be in the same plane.  One who has no experience with lining wheels should seek an experienced person to do it.  I have personal experiences with having seen my efforts fail only because of lack of experience.  An experienced person can show you what to do and what to be concerned with.

Blade guides rubbing on the blade will rob horsepower and blade speed. (I'm not talking about the necessary lip on the back of rolling guides.)

Driving the blade too fast for the amt. of horseposer your engine possesses will cause a slowing of the blade and, in effect, rob horsepower.

Lack of lubricant on the blade will cause friction in the cut and rob horsepower.  Lubricant on the belts may cause slippage.

Miss-set teeth will cause friction in the kerf and rob horsepower.  Too little set and the blade body rubs. Too much set and unnecessary amounts of wood will have to be removed. An off-set and the blade will raise or lower in the kerf, rubbing the blade body and scrub off horsepower.

Too little tension will cause the crowning of the blade in the cut.  This causes friction and robs horsepower.  
(The blade enters and exits the cant at the proper height but rises or sinks inside of the cant causing a convex or concave surface.}

Lack of beam strength in the blade or lack of driving support by the guides and the blade will bend toward its back and not only eventually destroy the blade but rob horsepower to the cut as it does it.

My personal preference would be steel.

[EZ]

Tom,
Thanks you for the educational reveiw, but I pretty much have all this covered. I dont mean to sound like a Mr know of all, but I went threw almost all of this when I was starting out. Some of this I really learned the hard way.
About the band wheels, the reason I ask about aluminum from steel is because, when I was in the drag racing thing the more hp I wood get out of my engine, the heavier the flywheel I wood make for the car, which the less rpm I wood lose when shifting. I realize that there is a big different from 1000 hp car & my 16 hp sawmill. But dont you think that once the rpm is up on the mill with steel wheels that they wood act like the flywheel on a car. I dont really know, I'm just wondering.
Thanks.
EZ

[wiam]

I would have to agree with Tom.  Heavier wheels would help going into a cut but once your in the cut you are using about all the hp you have so  there would be no difference.
William

[solidwoods]

I agree the flywheel stored inertia is not of significant value when applied to a bandsaw.  
The extra weight of a wheel that is heavier than necessary would become a liability.
      Wheels are rated for torque ability on the spokes or body and the mechanism that lock it too the shaft.  As long as you do not exceed the pwr/tq limitations of the wheel, a light weight wheel should be more power recovery efficient.  
 8)Mo run
 8)Fo
 8)Mo fun
The slow going cutting...???
If you have seen other people cut then you will have an idea of your machines performance (as compaired to another band contraption), I don't know if you have.
Any time I have a cutting performance problem, I back off all Blade  guides and prove the blade is running true to the wheels, also said as "the blade track" is proper.
yes power offfffff. ;)
  Reinstall guides .
Were talking about a proper flat cut right?,  not a bowed cut..This eliminates teeth off set
If the blade is low mileage (yai'nt cut much)
Belt slipping or looks like a Luffa sponge?  
Run the math on your blades feet per min, make sure it's right (or whatever you want it to be) just because it's shaped like a bandsaw doesn't mean some of the basic run stuff was set up for best or optimal performance.
My thoughts on blade speed.  Run the heck out of it..or at the upper end of it's fpm. limits.
And buy cheap blades.
 My Kasco has a 16hp brigs vanguard and I would say no problem with 30" cuts in Oak.
 
If all above checks ok, look at the blade. Low time...Yes.  
Full gullet sharpened?
How many teeth per inch?  I would use 7/8"
What set is on the blade..I set .028 each tooth for hard woods.
 I think Timberwolf sells a hand held tooth set measuring device (that is what I use). It really helps knowing what the set is. If you saw oak with a well used blade the set could be going out rather quick.  If the blade is sharp but low set, reset rerun.  
Save .5% of all money you make with the mill and buy an auto sharpener.
I started out using a chop saw type blade grinder, it only sharpens the face of the tooth.
Holy Cow..  Those things should be outlawed.  After a couple of sharpenings, I had deformed the profile of the gullet (at the molecular level) causing a whole bunch of sawdust neuclear rocket science crap to happen.  I would sharpen the blade, set teeth, run it very little,  DUD. Back to the drawing board.  ...Took me a year to figure that one out.
When you have your own sharpener,  a whole bunch of problems will go away.  Setting up the mill basics is easy (engine run,no slip to wheels,blade true,guides set,cut) but the poor guy at the front of the show is: .
When you sharpen your own blades,  you will learn how to tune it to run sweet on your machine.  As soon as it shows a sign of dull, take it off.  You will get better WPH (wood per hour) by running blades in the prime of there sharpness.  Cost is low for you to sharpen.  You could take a few customers blade sharpening, like I do.  Or put someone on the grinder, on piece work pay.

Gotta go, I hear the wife comming up the porch.
JIM

[EZ]

Gee, I guess I should have said it's kinda slower than I wood like it to be. Its not like I fall a sleep while sawing,  ;D.I guess I should be sawing instead of thinking, but I'm waiting for the load of logs I bought, o-boy, that could be another story.
EZ

[Tom]

Not intending to challenge your knowledge, EZ.  Just displaying some of my meager learnings.  Sometimes one thing leads to another and before I know it, I'm asleep.

[EZ]

Knowledge is something my pea-brain is missing, but I'm trying. Thanks Tom.
EZ

[solidwoods]

I had a grunt when I read the part about   heavy wheels helping on cut entry.  I make  entry of the blade into wood  slower than the normal feed rate.  As the teeth enter the wood, there isn't as much blade support as compared to the blade in mid cut (call it that? ) until the whole width of the blade is in the kerf, I slow the feed. And this is a matter of how much feed feel you have with your mill.  That's why you don't over power the feed system.  I like a feed system that allows the operator to feel the resistors to feed (knots, tough spots etc.), so that the operator can add just enough feed to continue. Not too fast or the blade could dive/dip not too slow or you will be "filing the wood" and making a slew of reasons why your not getting enough BPH (boards per hr.) and short blade life.  I know we are not talking about slamming the blade into the wood at full feed rate (some saws can do that ) so going slow to enter the blade shouldn't need any extra inertia from anything (except to overcome carburetor/engine lag..blah..blah.blah.)

As far as how your mill is performing, if you can work with another mill or two, it really gives you an idea of other performance capabilities.

Go easy into the wood.
And it will go easy into you.
Kornfusus.

[Tom]

Your right Solidwoods.  Entry into the log should be slower than feed rate  That's a good practice to get into regardless of the size mill you run.

 I was thinking that "torque" would only be valuable at entry into the log because, as you encrease the feed to an optimum rate, you use up the energy stored in the wheels until eventually it's the engine providing all the energy.

Perhaps a heavier wheel would help to get through spots of dense wood before the engine got up against the governor and provide a smoother speed rate but I just can't see wheel weight making much difference otherwise.

Hmmmmm maybe we're saying the same thing. :D

[wiam]

I think we are all saying about the same thing.It is not inertia but having the governor response adjusted properly.

William

[Jeff]

Same goes for big circle mills. We start slow.

[Tom]

Oh yeah, inertia.   That was the other word I wanted to use. :D

[Bro. Noble]

Tom,
 
Is that the kinitic type of energy?

Noble

[Tom]

 :P :P :P :P :P hmmmmmm :P kinetic.. yep :P :P nope...not potential cause inertia is movement...or lack of movement.. energy has to effect it somehow.  that's where you get "work" :P^{WORK ? ! ? !}  
That big steel wheel is potential energy and when it's spinning it's kinetic energy that makes it turn ....is there going to be a test?......and inertia is that resistance to movement that the energy is applied and when it's cutting the potential energy turns into kinetic energy and the work ^{WORK ! ? ! ?} causes the resistance that creates the inertia that stops the wheel.

........i think..   I'm getting confused ??? :P   ZZZ-Z--Z---Z---z----z----z---z--z

[EZ]

When I first started sawing with a bandmill the mill was an old piece of junk. A good day was 200 bf, it had a 5 hp on it that was just about done for. When I got my Baker doing what I expected it to do, I had a hard time with the feed rate, because of the movies I order. I wood time their saw & try to match the feed rate, it just seemed like I was going to slow. I wood speed up my rate & saw for awhile like that. Then I wood start thinking about the movies I watch & timed, I'd slow down again. It did'nt matter if I was going fast or slow the lumber was nice & strait, but I still thought I was doing some thing wrong. So when I had a chance to go to a band mill show, that help out alot. I couldnt beleave how slow these guys where sawing, I ask the one dealer if I could push it threw, he put a new blade on & I sawed it like I saw with mine. I look at the board & it was wavy all the way down, he said I push to fast, so I try it again, same thing.
EZ

[Tom]

I guess a mill is like an old pair of shoes.  The more you wear them the better they feel.  I've found that most folks using an unfamiliar mill will feed real slow.  Some of these "show" machines may not be set up real good too.  I've seen some real Yo-Yo's tending the booths and you get the feeling that they haven't a clue.  On the other hand,  I've visited booths and learned a lot.  It's a shame that we can't always tell that we are listening to experience. :-/

I was asked once, because I was having a problem, "how many feet per minute do you feed".   I had no idea.  I had never thought to measure how fast the saw was traveling down the track because I sawed so many different diameters of logs.  I mostly listened to the saw and the engine.  I guess I came across as a dim-wit but it just never entered my mind to use a stop watch.  Perhaps your watching the movie was akin to that and they were sawing a little log. :-/

I still swear by a sharp tooth.

I've a friend with an EZ who cut his teeth on a circle mill.  His biggest complaint is the speed of the saw.  I would tell him that he had to forget that big diesel powered circle mill and take his time.

One day I sharpened a blade for him to try and he was grins from ear to ear.  "I don't even have to push it",  he said.

Then he started telling me how he didn't like the aluminum because he couldn't weld it.  He had made a new track for the mill that was about 40' long out of steel and wanted to change some of the things on the mill head but couldn't.  That aluminum mill does come in handy if you move it frequently though.  It is nothing to put it in the back of a pick-up.

I'll have to admit that, after running a mill with feed motors, log handling equipment and bigger engines,  I would have a hard time being happy with a push mill of any manufacture.

[MrMoo]

I just read the replies to the thread.

Given that you have a sharp blade and things are runninng good can the aluminum wheels be an issue because they might be more prone to flex? Is it possible that with aluminum being softer and with the tension on the blade they could flex out of their plane?
I use to work as a tool and die maker and while aluminum was great to machine if we wanted strength and rigidity we went with steel or stainless in demanding situations.
Just my $0.02.

[Tom]

I never thought of that.

Bands run on automobile tires though and they move around. I know what you are saying,  it's probably not the same thing.   Aren't there differnt aluminum alloys that give rigidity?  I have used aluminum for things and found it brittle.  Not being a metalurgist, I don't know why. :P

[MrMoo]

Tom,
You're right there are different AL alloys, I forgot about that.  :-/ Some do have more strength than others. I'm also not sure what happens when you cast AL.
I guess I'd prefer steel but if something works and you get good results its hard to argue with that.
Just another thought if the wheels flexed a bit would it cause shorter blade life? I'm not sure if its even worth considering that given all the other stresses a blade goes thru.
Mike

[EZ]

My guess is the aluminum wheels are a heavyer cast, I've taken them off a few times & they are heavy. Next time I take one off I'll have to weigh it.
The only thing I dont under stand is on the idle side, the built is loose until I fire the mother up & run it for a minute, then it's tight in the grove. Any body have any idea why this is.
EZ

[ADfields]

A part made of aluminum MUST be thicker than if it were made of steel to do the same job, take the same load.   This makes the aluminum part flex less as well as still being less weight.   Casting aluminum is no big deal and will not change the makeup of it like iron, it's non faros and works more like copper or lead.   I have always found aluminum very hard on tools when machining it, it likes to get gummy and weld it's self to the cutting edge of tools witch will dull them fast.   The other bad thing about aluminum is it will fatigue and become brittle way faster than steel, this is why wings fall from aircraft and no one ever sees a crack or other symptom first.   Aluminum makes the best heavy truck wheels as they are thicker and flex a lot less than steel with makes them stronger and less likely to fail in the end.   I would be glad to have aluminum band wheels on my mill, I think it would be the best way to go.
Andy